It’s not often that a showbiz melodrama plays out so neatly inside a week, like an earthy four-part BBC drama, or a bout of the trots. But the past seven days have given us the perfect celebrity serial: one that began with a tabloid exposé and ended with Jack Whitehall kink-shaming live on ITV. This, of course, is the ballad of Cheryl-doesn’t-currently-have-a-surname and Liam Payne.

To understand the breakdown, though, you have to understand the genesis of a slightly creepy relationship. Cheryl first met Liam when she was a 24-year-old X Factor “mentor” and he was a 14-year-old schoolboy in bootcut jeans and an ill-fitting waistcoat singing Fly Me to the Moon in order to win her vote and get through to bootcamp. There is a moment in that initial audition when he half winks at her and she smiles – to the viewer at the time, it was just a tween’s mam-taught approximation of rat-pack-performing patter, but we now know that Liam was thinking: “Just wait one decade until I get you pregnant and we name our son Bear.”

It’s often the cry of teachers, professors or Woody Allen that when they start to date someone a decade their junior, the object of their affections is “actually very mature for their age” – a kind of older man oath of allegiance, if you like: I do solemnly swear that, admittedly, Kirsty might still have pigtails but honestly we watched Only Connect the other night and she got two of the answers right.

Yet Cheryl would be forgiven for believing that Liam was not just mature for his age but near-geriatric. If Harry was the rebellious one, and Zayn the sexy one, then Liam was the Iain Duncan Smith of One Direction. His personality was not to have one, his hobby was breathing. He was a man for whom the peak of excitement was his morning shower – so much so that he once actually tweeted: “woop woop shower time.”

Still, after two failed marriages with a love-rat footballer and a man with twice as many names as a man should have (Jean-Bernard Fernandez-Versini), you can see why Cheryl might have wanted to keep things simple with two syllables from Wolverhampton. Besides, she’s a six-time Will.I.Am collaborator. Once they were together she could help him become a bit cooler. She could have it all: a malleable handsome young pop star exterior, with a hard Werther’s Original core.

If that was the plan, it went awry: according to the tabloids, Cheryl has barely left the house in the past nine months as she cares for their child. Liam, meanwhile, is gallivanting across the world touring an album of sexless R&B, dressing like Kevin Federline and talking as if he’s on My Super Sweet 16 and he’s really chuffed off because Daddy promised he was going to get Kendrick Lamar for the party but in the end only Rizzle Kicks showed up.

A particular nadir was when Liam – a man who, just three years earlier, told fans “I wish I was Harry Potter” – Instagrammed a photo of himself wearing a red tracksuit and gold chain, with his middle finger flipped at the camera and the caption: “You can only get jet lag from a jet the rest of yall have got plane lag.” The post was eventually deleted, but the message was clear: in an attempt to refresh his image, he had somehow become even less cool than when he was sweeping his fringe out of his eyes and singing Frank Sinatra for the delectation of Louis Walsh.

Yet most observers thought Cheryl was grinning and bearing it, mostly because the grin’n’bear is the only facial expression she has exhibited this decade. But on Sunday, the Sun splashed on an exclusive that the couple were having “SPLIT TALKS”.

Apparently Liam’s now considerable ego has been bruised after he has made repeated wedding proposals, all of which have been knocked back by Cheryl. It is perfectly understandable: as she juggles two children, infant and infantile, Cheryl might not be that keen on a third marriage right now. But the paper reported that the rebuffings have created an unhealable rift and Liam has consulted his financial advisors to see what a split would cost.

Then, on Tuesday, Cheryl appeared on BBC Breakfast to launch her new charitable foundation, Cheryl’s Trust. Host Dan Walker asked her if it was “frustrating, when you’re trying to focus on what you’re doing there, when so much of your personal life is in the papers at the moment?”, thus creating the very frustration he was referring to while making it seem like he is somehow above the scum of the tabloids. Cheryl, a dab hand at telling someone to eff off with a single doe-eyed stare, just repeated the question back at Walker. “Is it frustrating?” she spat – waiting to see if he might just shrink back into the sofa. “No, it doesn’t bother me at all.”

The next obstacle was trickier to stage-manage: the Brits, music’s biggest night! Liam and Cheryl were both due to attend, yet they hadn’t been seen together in months. They would have to go separately and announce to the world that it was over.

But hours before the Brits, Liam’s Instagram revealed the two of them enjoying a spontaneous moment of affection, Cheryl lying on the sofa fiddling with Liam’s nose. Lucky it was caught on Liam’s personal account by a third person filming the well-framed shot from the other side of the room. There is surely no irony that Justin Timberlake’s new single plays in the background with its refrain of “haters gonna say it’s fake”.

Then, at the awards proper – which were hosted by Jack Whitehall, despite him being the living antithesis of current movements demanding more diversity at awards shows; I mean, you literally might as well get Andrea Leadsom to host the Mobos – their love was put under further scrutiny. Liam was performing a song from the 50 Shades Freed soundtrack with Rita Ora. So Whitehall, sidling alongside them at their table, wanted to know what their “safe word” was? There was an open goal for a cheap gag here: “The baby monitor is our safe word!!”, if you’re playing it safe. “Nightclub toilet,” if you’re feeling risky. Instead, Cheryl said it was “Don’t stop” – in a kind of solemn overcompensation for how kinky and totally fine their sex life is - although I’m pretty sure people who use safe words don’t joke about no meaning yes.

As if to add further distraction, Este from Haim was sitting behind Liam, dramatically applying lip gloss and making “call me” signals behind her head. It had a kind of Carry On brilliance, the funniest thing to happen at the whole Brits, but perhaps sensing that she had cracked a gag at a funeral, Este phoned Cheryl live on the Radio 1 Breakfast Show the next morning to let her know there was no bad blood.

Thursday’s tabloids were full of Liam and Cheryl’s “brave faces”, suggesting that the story will end happily. Right on cue, Dan Wootton’s Bizarre column in the Sun – the British tabloids’ pot-stirrer-in-chief – weighed in to claim the whole thing was a stunt, and that his magic sources say the relationship is very strained.

Like all great dramas, and all great bouts of gastroenteritis, just when you think it’s over – a second series announces itself.